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• A421 Bedford to M1 Junction 13

Protecting the Environment

Ecological and archaeological surveys have already taken place along the line of the new A421. Before construction could start full archaeological investigations have been undertaken.

During construction ecologists and archaeologists will continue to monitor site activities. This will ensure we minimise the effects of the works on both natural and cultural heritages.

There are a number of water courses along the A421. These will be monitored and measures put in place to prevent any contamination due to the works.

We will plant about 250,000 new trees and shrubs which, as they mature, will help to blend the new road into the surroundings.

As many of these trees as possible will be sourced from the Marston Forest.

Update January 2010

Landscaping

We have planted 11,325 specimens of various species such as Maple, Alder, Siver Birch, Dogwood, Hazel, Hawthorn, Ash, Privet, Crab Apple, Black Poplar, Wild Cherry, Blackthorn, English Oak, Blackberry, Willow, Black Elder and Mountain Ash.

The bulk of the planting work has taken place at Junction 13, throughout Brogborough cut, Wood End Bridge and the approach to the new Marsh Leys Bridge.

Some background information -

• The planting season is November to March.
• We are currently planting 2,000 specimens a day.
• Bedford sits in the intersection of three regional provenance zones (zones 403, 402 and 405).  we have employed nurseries from each zone to promote the growth of hardy stock that compliments the natural ecological balance of the area.

World Environment Day 2009 - The A421 project pledged to donate 1 tree for every person working on site that day.  During National Tree Week on Sunday 6 December, 115 trees out of the 360 we had adopted were planted. Trees were a mixture of Oak, Silver Birch, Cherry amongst others.  Surrounding these, shrubs were to be planted.

Archaeology

Archaeological fieldwork is now coming to an end, although there are currently two excavations being carried out along the route. Archaeological remains dating to the Roman Period (2 - 3rd Century AD) have been found. Features include settlement activity in the form of field boundaries, pits, and quarries. Also relating to this historic period, pottery, metal objects, and bone have been found.

Another site, this time dating from the Iron Age (1 - 2nd Century BC) has also been discovered. This site might have been a farmstead and includes many ditches and pits. Following the conclusion of fieldwork along the proposed scheme a full report will be produced and made available to the public through Bedfordshire Borough Council's Sites and Monument Record. 

Recycle

Pulverised Fuel Ash (PFA)

We have received a great deal of interest about the fill material we have used near to M1 Junction 13.

PFA is the result of burning of pulverised bituminous, hard coals in power station furnaces. PFA has been used as a lightweight fill material to construct the embankment for the new M1 Junction 13 Brogborough Interchange.

To be able to use PFA the Project had to register with the Environment Agency, an exempt activity under Paragraph 19 of the Environmental Permitting Regulations 2007

Prior to importing the PFA the Broughton Brook watercourse was realigned to its new permanent route to minimise the potential for any pollution to occur with regular visual inspections and water clarity monitoring taking place.

On completion of the new embankment approximately 375,000 tonnes of PFA have been imported to site over a 5 month period from Ratcliffe and Didcot power stations - peaking at 30,000 tonnes per week.

Key benefits of using PFA at the A421 Project include:

• Diverting of PFA from Landfill
• Reduction in the use of Primary Aggregates
• Readily available in large quantities within reasonable transport distances
• PFA is primarliy alumino-silicate glass with low trace elements present
• PFA has low permeability making it difficult for trace elements to be leached

Tyre Bales

In the UK alone it is estimated that up to 40 million vehicle tyres reach the end of their life each year. Traditionally much of these were sent to landfill for disposal. In 2003 a ban of disposal to landfill was introduced and therefore alternative environmentally friendly solutions were required.

Recently, uses in engineering & construction have begun to be introduced. Typically this has been to use tyre bales as an alternative to traditional fill materials.

So far, uses of tyre bales have been for small projects and these uses include:

• aiding slope stabilisation to prevent erosion or landslips
• used as a fill in constructing minor roads for light traffic flow
• as waterway & flood control barriers
• recreational projects e.g. golf course landscaping

Here at the A421 Project the use of tyre bales has been dramatically scaled up to help build a lightweight embankment on soft ground next to Brogborough Lake to allow the re-alignment of the existing A421.

Each tyre bale is about 1.5m x 0.8m x 1.3m in size and consists of around 100 - 115 tyres. In building the new embankment it is estimated that 4500 tyre bales will be required during this work, equating to around 500,000 tyres.

The tyre bales used on the A421 conform to relevant standards, so there is no threat to public health or the environment. This is just one example that shows how the A421 Project team is employing innovative engineering techniques whilst also working to protect the environment.

A 14m deep cutting is underway at Brogborough. The material from this is being used to form alignments of the southbound off-slip from the M1 and the new Salford Road.

Ecology

Spring 2009 saw the emergence of great crested newts from hibernation, allowing ecologists to return to the site and re-home them. A further 116 great crested newts were safely moved this spring, bringing the scheme total to almost 400. As part of the same process around 3500 common amphibians (frog, toad and smooth newts) have been captured from land within the route corridor and released into retained areas of suitable habitat.

The discovery of a new badger sett within the route corridor during winter gave the project team a challenge. Badgers breed during the winter months and in order to prevent harm to young it is not normally possible to gain a licence to close a sett during the winter months.

Following close correspondence with Natural England a variety of methods were utilised to investigate the sett. This included the use of night vision and fibre optic cameras mounted on remote controlled vehicles.

Through this we were able to demonstrate that the sett had not been used for several weeks which meant the sett could be closed under licence from Natural England.

Use of these novel techniques has prevented a possible delay to works on this scheme and crucially ensured that no badgers were harmed.

Renew

The 5th of June 2009 was the United Nations Environment Programme (UNEP) annual World Environment Day. The A421 project contribution to this day & UNEP Plant for the Planet: Billion Tree Campaign has been to pledge to plant a tree for every member of staff on site that day. We are delighted to announce that 360 new trees will be planted locally in the Forest of Marston Vale.